While promoting her book, "Now It's My Turn: A Daughter's Chronicle of Political Life," Mary Cheney had told People that she was in favor of legalized same-sex marriage.
She was one of her father's top campaign aides and one of his closest confidantes. In July 2003, she became the director of vice presidential operations for the Bush-Cheney 2004 re-election campaign.
The identity of the baby's father was not known.
Notable deaths of 2014 [PHOTOS]
Sophia Loren celebrates 80th birthday